If you're hoping to track down the golden Mario amiibo, this Wal-Mart poster spotted by the amiibo reddit suggests you're going to have a hard time. It's not even out yet, and it's already rare! Good luck!
Pre-orders for the Metal Gear Solid 5 Collector's Edition are also sold out for both consoles on Amazon. Thank god I checked randomly yesterday otherwise I'd have to pay some scumbag scalper if I wanted it. What a surprise too! They're all on eBay (pre-orders, mind you) for upwards of $200.
Unbelievable how quickly things disappear. This is getting really shitty, and it's not just a Nintendo problem.